Pump arrangements are known in which a liquid is fed by gravity to the inlet of a pump which is operative to discharge the liquid as out an outlet.
As but one example of the prior art, U.S. Pat. No. 8,071,933 to Ophardt, issued Dec. 6, 2011 illustrates a dispensing system for dispensing liquid, most preferably, hand cleaning fluid from a liquid reservoir. The liquid is gravity fed from a liquid reservoir to a piston pump and discharged via a piston of the piston pump being reciprocally moved in a piston chamber. The piston is moved by an actuator which engages the piston and the actuator being moved by the rotation of a motor connected to the actuator by a centric cam. The reservoir and its attached piston pump assembly are adapted to be removed and replaced when the liquid in the reservoir is exhausted. The present applicant has appreciated the disadvantage with such prior art devices that in a case when the liquid in the reservoir is exhausted, the dispenser is continued to be operated by a user and with time, the resistance to movement of the piston can substantially increase with resulting damage to the motorized activator assembly including the actuator, the motor and coupling mechanisms between the motor and the actuator such as gear arrangements, centric cams and the like. Damage to the actuation system is disadvantageous since the actuation system is to remain in the dispenser for continued use for an extensive time without replacement
Prior art dispensers are known which simultaneously dispense a first liquid from a first liquid source and a second liquid from a second liquid source. Proper operation of any such prior art devices require the simultaneous dilution of both liquids.
A disadvantage of such known devices is that when the source of one of the two liquids is exhausted, the pump arrangement continues to dispense the other liquid with the disadvantage that the resultant product is not the mixture intended to be discharged.
Prior art devices are known in which two liquids from two sources are to be simultaneously dispensed and at least one of the liquids in its form prior to mixture has a disadvantage associated with it when discharged without the other liquid. For example, one of the liquids may be a concentrated cleaner which, by itself, would be hazardous as in being corrosive and otherwise detrimental when used alone, and the second fluid may be a diluent such as, for example, water which when mixed with the first liquid renders the liquid mixture safe for an intended use. The applicant has appreciated the disadvantage that in a pump arrangement for dispensing both the first concentrate liquid and the second diluent concentrate that if the supply of the diluent liquid becomes empty, the pump arrangement may discharge merely the concentrate liquid presenting a hazardous disadvantage. As well, the applicant has appreciated the disadvantage that should the supply of the concentrate liquid be empty, the disadvantage arises that the pump arrangement will continue to dispense merely the diluent liquid having the disadvantage of the delivering a product which is different than the product intended.
The present inventors have appreciated that known self-dilution pump arrangements that are to discharge two liquids suffer the disadvantage that they do not provide simple and inexpensive mechanisms to ensure that when either one of two liquids is exhausted that dispensing of both liquids is stopped.
In one aspect, the present invention provides a pump arrangement comprising:
a first piston pump having a first chamber and a first piston reciprocally movable along a first axis in the first chamber to draw a first fluid into the first chamber from a first reservoir through a first conduit opening into the first chamber and discharge the first fluid out a first outlet,
a first float valve across the first conduit between the first reservoir and the first chamber,
the first float valve including a first float movable between an open condition and a closed condition,
the first float buoyant in the first fluid,
the first float assuming the open condition when a level of the first fluid in the first conduit is above a predetermined first fluid float level,
the first float assuming the closed position when a level of the first fluid in the first conduit is at or below the predetermined first float level,
with the first float in the open condition, the first float valve permitting for flow in the first conduit from the first reservoir to the first chamber,
with the first float in the closed condition, the first float valve preventing flow in the first conduit from the first reservoir to the first chamber,
with the first float in the closed position, reciprocal movement of the first piston creates a vacuum condition in first chamber between the first float valve and the first piston,
a driving member movable reciprocally parallel to the first axis,
the driving member adapted to be coupled to an actuator which moves the driving member reciprocally parallel to the first axis,
a releasable juncture arrangement releasably coupling the driving member and the first piston together, the releasable friction juncture arrangement having a coupled condition and an uncoupled condition,
in the coupled condition, the releasable juncture arrangement couples the driving member and the first piston together such that reciprocal movement of the driving member parallel the first axis moves the first piston member parallel the first axis in unison,
in the uncoupled condition, the releasable juncture arrangement does not couple the driving member and the first piston together such that reciprocal movement of the driving member parallel the first axis does not move the piston member rendering the first piston pump inoperative to discharge the first fluid by movement of the driving member,
with the releasable juncture arrangement in the coupled position, when the vacuum condition in the first chamber is greater than a threshold separation vacuum, the releasable juncture arrangement assumes the uncoupled position.
Preferably, the pump arrangement of the first aspect includes a second piston pump having a second chamber and a second piston reciprocally movable along a second axis in the second chamber to draw a second fluid into the second chamber from a second reservoir through a second conduit opening into the second chamber and discharge the second fluid out a second outlet,
the second axis parallel to the first axis,
a second float valve across the second conduit between the second reservoir and the second chamber,
the second float valve including a second float movable between an open condition and a closed condition,
the second float buoyant in the second fluid,
the second float assuming the open condition when a level of the second fluid in the second conduit is above a predetermined second fluid float level,
the second float assuming the closed position when a level of the second fluid in the second conduit is at or below the predetermined second float level,
with the second float in the open condition, the second float valve permitting for flow in the second conduit from the second reservoir to the second chamber,
with the second float in the closed condition, the second float valve preventing flow in the second conduit from the second reservoir to the first chamber,
with the second float valve in the closed position, reciprocal movement of the second piston creates a vacuum condition in second chamber between the second float valve and the second piston,
a coupling bridge member mechanically linking the first piston and the second piston together to form a driven member carrying the first piston and second piston mechanically linked with the bridge member for movement in unison parallel the first axis,
the driving member coupled to the driven member by the releasable juncture arrangement,
in the coupled position of the releasable juncture arrangement, the releasable friction juncture arrangement securing the driving member and the driven member together for reciprocal movement along the axis in unison,
in the uncoupled position of the releasable juncture arrangement, the movement of the driving member does not move the driven member rendering both the first piston pump inoperative to discharge the first fluid by movement of the driving member and the second piston pump inoperative to discharge the second fluid by movement of the driving member,
with the releasable juncture arrangement in the coupled position, when either the first vacuum condition is greater than the threshold separation vacuum or the second vacuum condition is greater than the threshold separation vacuum, the releasable juncture arrangement assumes the uncoupled position.
In a 2nd aspect, the present invention provides a pump arrangement comprising:
a first piston pump having a first chamber and a first piston reciprocally movable along a first axis in the first chamber to draw a first fluid into the first chamber from a first reservoir through a first conduit opening into the first chamber and discharge the first fluid out a first outlet,
wherein reciprocal movement of the first piston discharges the first fluid from the first reservoir until the first reservoir is empty of the first fluid wherein further reciprocal movement of the first piston creates a vacuum condition in first chamber axially inward of the first piston,
a driving member movable reciprocally parallel to the first axis,
the driving member adapted to be coupled to an actuator which moves the driving member reciprocally parallel to the first axis,
a releasable juncture arrangement releasably coupling the driving member and the first piston together, the releasable friction juncture arrangement having a coupled condition and an uncoupled condition,
in the coupled condition, the releasable juncture arrangement couples the driving member and the first piston together such that reciprocal movement of the driving member parallel the first axis moves the first piston member parallel the first axis in unison,
in the uncoupled condition, the releasable juncture arrangement does not couple the driving member and the first piston together such that reciprocal movement of the driving member parallel the first axis does not move the piston member rendering the first piston pump inoperative to discharge the first fluid by movement of the driving member,
with the releasable juncture arrangement in the coupled position, when the vacuum condition in the first chamber is greater than a threshold separation vacuum, the releasable juncture arrangement assumes the uncoupled position.
In a 3rd aspect, the present invention provides a pump arrangement comprising:
a first piston pump having a first dispensing chamber and a first piston element reciprocally movable along a first axis in the first dispensing chamber to draw a first fluid into the first dispensing chamber from a first reservoir through a first conduit opening into the first dispensing chamber and discharge the first fluid out a first discharge outlet,
the first piston pump including a first inlet one-way valve across the first conduit, the first inlet one-way valve providing for flow of the first fluid from the first reservoir to the first dispensing chamber but preventing flow of the first fluid from the first dispensing chamber to the first reservoir,
wherein reciprocal movement of the first piston element discharges the first fluid from the first reservoir until the first reservoir is empty of the first fluid wherein further reciprocal movement of the first piston element creates a first vacuum condition in first dispensing chamber axially inward of the first piston element,
first piston element including a driven member,
a driving member movable reciprocally parallel to the first axis,
a releasable juncture arrangement releasably coupling the driving member and the driven member together, the releasable juncture arrangement having a coupled condition and an uncoupled condition,
in the coupled condition, the releasable juncture arrangement couples the driving member and the driven member together such that reciprocal movement of the driving member parallel the first axis moves the first piston element parallel the first axis in unison,
in the uncoupled condition, the releasable juncture arrangement does not couple the driving member and the driven member together such that reciprocal movement of the driving member parallel the first axis does not move the piston element rendering the first piston pump inoperative to discharge the first fluid by movement of the driving member,
with the releasable juncture arrangement in the coupled position, when the first vacuum condition in the first dispensing chamber is greater than a threshold separation vacuum, the releasable juncture arrangement assumes the uncoupled position.
In a 4th aspect, the present invention provides the pump arrangement of the 3rd aspect, wherein the driving member is adapted to be removably coupled to an actuator member which moves the driving member reciprocally parallel to the first axis,
a first float valve across the first conduit between the first reservoir and the first dispensing chamber,
the first float valve including a first float movable between an open condition and a closed condition,
the first float buoyant in the first fluid,
the first float assuming the open condition when a level of the first fluid in the first conduit is above a predetermined first fluid float level,
the first float assuming the closed position when a level of the first fluid in the first conduit is at or below the predetermined first float level,
with the first float in the open condition, the first float valve permitting for flow in the first conduit from the first reservoir to the first dispensing chamber,
with the first float in the closed condition, the first float valve preventing flow in the first conduit from the first reservoir to the first dispensing chamber,
with the first float in the closed position, reciprocal movement of the first piston element creates the first vacuum condition in first dispensing chamber between the first float valve and the first piston element.
In a 5th aspect, the present invention provides the pump arrangement of the 4th aspect, the first float valve is across the first conduit between the first reservoir and the first inlet one-way valve.
In a 6th aspect, the present invention provides the pump arrangement of any one of the 3rd to 5th aspects, and wherein the first reservoir is unvented and collapsible.
In a 7th aspect, the present invention provides the pump arrangement of any one of the 3rd to 5th aspects wherein the first reservoir is vented to the atmosphere.
In an 8th aspect, the present invention provides the pump arrangement of any one of the 3rd to 7th aspects including:
a second piston pump having a second dispensing chamber and a second piston element reciprocally movable along a second axis in the second dispensing chamber to draw a second fluid into the second dispensing chamber from a second reservoir through a second conduit opening into the second dispensing chamber and discharge the second fluid out an outlet selected from the first discharge outlet and a second outlet,
the second axis parallel to the first axis,
the second piston pump including a second inlet one-way valve across the second conduit, the second inlet one-way valve providing for flow of the second fluid from the second reservoir to the second dispensing chamber but preventing flow of the second fluid from the second dispensing chamber to the second reservoir,
wherein reciprocal movement of the second piston element discharges the second fluid from the second reservoir until the second reservoir is empty of the second fluid wherein further reciprocal movement of the second piston element creates a second vacuum condition in second dispensing chamber axially inward of the second piston element,
a coupling bridge member mechanically linking the first piston element and the second piston element together for movement in unison parallel the first axis and forming the driven member,
in the uncoupled position of the releasable juncture arrangement, the movement of the driving member does not move the driven member rendering both the first piston pump inoperative to discharge the first fluid by movement of the driving member and the second piston pump inoperative to discharge the second fluid by movement of the driving member,
with the releasable juncture arrangement in the coupled position, when either the first vacuum condition is greater than the threshold separation vacuum or the second vacuum condition is greater than the threshold separation vacuum, the releasable juncture arrangement assumes the uncoupled position.
In a 9th aspect, the present invention provides the pump arrangement of the 8th aspect including:
a second float valve across the second conduit between the second reservoir and the second chamber,
the second float valve including a second float movable between an open condition and a closed condition,
the second float buoyant in the second fluid,
the second float assuming the open condition when a level of the second fluid in the second conduit is above a predetermined second fluid float level,
the second float assuming the closed position when a level of the second fluid in the second conduit is at or below the predetermined second float level,
with the second float in the open condition, the second float valve permitting for flow in the second conduit from the second reservoir to the second dispensing chamber,
with the second float in the closed condition, the second float valve preventing flow in the second conduit from the second reservoir to the second dispensing,
with the second float valve in the closed position, reciprocal movement of the second piston element creates the vacuum condition in second dispensing chamber between the second float valve and the second piston element.
In a 10th aspect, the present invention provides the pump arrangement of the 9th aspect wherein:
the second float valve is across the second conduit between the second reservoir and the second inlet one-way valve.
In an 11th aspect, the present invention provides the pump arrangement of the 8th, 9th or 10th aspect wherein the second reservoir is unvented and collapsible.
In a 12th aspect, the present invention provides the pump arrangement of the 8th, 9th or 10th aspect wherein the first reservoir is vented to the atmosphere and the second reservoir is vented to the atmosphere.
In a 13th aspect, the present invention provides the pump arrangement of any one of the 3rd to 12th aspects wherein the driving member and the driven member are mechanically engaged through a frangible member that severs when the applied tension force parallel the first axis is greater than a threshold tension force parallel the first axis.
In a 14th aspect, the present invention provides the pump arrangement of any one of the 3rd to 12th aspects wherein the driving member and the driven member are frictionally engaged with frictional forces preventing disengagement unless the applied tension force parallel the first axis is greater than a threshold tension force parallel the first axis.
In a 15th aspect, the present invention provides the pump arrangement of any one of the 3rd to 14th aspects wherein the releasable juncture arrangement is formed by the driving member and the driven member being engaged to prevent relative axial movement of the driving member relative the driven member by the application across the releasable juncture arrangement of an applied tension force parallel the first axis unless the applied tension force parallel the first axis is greater than a threshold tension force parallel the first axis.
In a 16th aspect, the present invention provides the pump arrangement of any one of the 8th to 15th aspects wherein:
the first float valve including a first valve seat about a first fluid outlet opening, in the closed condition, a surface of the first float sealably engages the first valve seat to prevent flow through the first fluid outlet opening to the first dispensing chamber, and the first float valve including a first cage structure constraining movement of the first float with the first cage structure, the first float movable in the first cage structure between the open condition and the closed condition,
the second float valve including a second valve seat about a second fluid outlet opening, in the closed condition, a surface of the second float sealably engages the second valve seat to prevent flow through the second fluid outlet opening to the second dispensing chamber, and the second float valve including a second cage structure constraining movement of the second float with the second cage structure, the second float movable in the second cage structure between the open condition and the closed condition.
In a 17th aspect, the present invention provides the pump arrangement of any one of the 3rd to 16th aspects wherein the first dispensing chamber having an open outer end,
the first piston element having a distal inner end coaxially slidable within the first dispensing chamber about the first axis,
the first piston element extending from the distal inner end outwardly through the open outer end of the first dispensing chamber to an outer end of the first piston element carrying the first discharge outlet,
a central passageway through the first piston element from the driven member to the driving member open to the first discharge outlet carried on the driving member.